bmp388: some cleanup

- avoid unnecessary sensor readout cycle during init
- check status register for data ready

src/drivers/barometer/bmp388/bmp388.cpp

@@ -92,20 +92,6 @@ BMP388::init()
 		return -EIO;
 	}
 
-	/* do a first measurement cycle to populate reports with valid data */
-	if (measure()) {
-		PX4_WARN("measure failed");
-		return -EIO;
-	}
-
-	/* sleep this first time around */
-	px4_usleep(_measure_interval);
-
-	if (collect()) {
-		PX4_WARN("collect failed");
-		return -EIO;
-	}
-
 	start();
 
 	return OK;
@@ -128,7 +114,7 @@ BMP388::start()
 {
 	_collect_phase = false;
 
-	ScheduleOnInterval(_measure_interval, 1000);
+	ScheduleOnInterval(_measure_interval, _measure_interval);
 }
 
 void
@@ -150,7 +136,7 @@ BMP388::measure()
 
 	/* start measurement */
 	if (!set_op_mode(BMP3_FORCED_MODE)) {
-		PX4_WARN("failed to set operating mode");
+		PX4_DEBUG("failed to set operating mode");
 		perf_count(_comms_errors);
 		perf_cancel(_measure_perf);
 		return -EIO;
@@ -184,11 +170,11 @@ BMP388::collect()
 	_px4_baro.set_error_count(perf_event_count(_comms_errors));
 
 	float temperature = (float)(data.temperature / 100.0f);
-	float pressure = (float)(data.pressure / 100.0f); // to hecto Pascal
+	float pressure = (float)(data.pressure / 100.0f); // to Pascal
 	pressure = pressure / 100.0f; // to mbar
 
 	_px4_baro.set_temperature(temperature);
-	_px4_baro.update(timestamp_sample, pressure); // to mbar
+	_px4_baro.update(timestamp_sample, pressure);
 
 	perf_end(_sample_perf);
 
@@ -260,15 +246,13 @@ static int8_t cal_crc(uint8_t seed, uint8_t data)
 bool
 BMP388::validate_trimming_param()
 {
-	bool    result = false;
 	uint8_t crc = 0xFF;
 	uint8_t stored_crc;
-	uint8_t trim_param[BMP3_CALIB_DATA_LEN];
+	uint8_t *trim_param = (uint8_t *)_cal;
-	uint8_t i;
 
-	memcpy(&trim_param, _cal, BMP3_CALIB_DATA_LEN);
+	static_assert(BMP3_CALIB_DATA_LEN <= sizeof(*_cal), "unexpected struct size");
 
-	for (i = 0; i < BMP3_CALIB_DATA_LEN; i++) {
+	for (int i = 0; i < BMP3_CALIB_DATA_LEN; i++) {
 		crc = (uint8_t)cal_crc(crc, trim_param[i]);
 	}
 
@@ -276,11 +260,7 @@ BMP388::validate_trimming_param()
 
 	stored_crc = _interface->get_reg(BMP3_TRIM_CRC_DATA_ADDR);
 
-	if (stored_crc == crc) {
+	return stored_crc == crc;
-		result = true;
-	}
-
-	return result;
 }
 
 uint32_t
@@ -345,7 +325,7 @@ BMP388::get_measurement_time(uint8_t osr_t, uint8_t osr_p)
 bool
 BMP388::set_sensor_settings()
 {
-	_measure_interval = get_measurement_time(_osr_t, _osr_p);
+	_measure_interval = get_measurement_time(osr_t, osr_p);
 
 	if (_measure_interval == 0) {
 		PX4_WARN("unsupported oversampling selected");
@@ -364,10 +344,10 @@ BMP388::set_sensor_settings()
 		return false;
 	}
 
-	/* Select the and over sampling settings for pressure and temperature */
+	/* Select the over sampling settings for pressure and temperature */
 	uint8_t osr_ctl_reg = 0;
-	osr_ctl_reg = BMP3_SET_BITS_POS_0(osr_ctl_reg, BMP3_PRESS_OS, _osr_p);
+	osr_ctl_reg = BMP3_SET_BITS_POS_0(osr_ctl_reg, BMP3_PRESS_OS, osr_p);
-	osr_ctl_reg = BMP3_SET_BITS(osr_ctl_reg, BMP3_TEMP_OS, _osr_t);
+	osr_ctl_reg = BMP3_SET_BITS(osr_ctl_reg, BMP3_TEMP_OS, osr_t);
 
 	ret = _interface->set_reg(osr_ctl_reg, BMP3_OSR_ADDR);
 
@@ -378,7 +358,7 @@ BMP388::set_sensor_settings()
 
 	/* Using 'forced mode' so this is not required but here for future use possibly */
 	uint8_t odr_ctl_reg = 0;
-	odr_ctl_reg = BMP3_SET_BITS_POS_0(odr_ctl_reg, BMP3_ODR, _odr);
+	odr_ctl_reg = BMP3_SET_BITS_POS_0(odr_ctl_reg, BMP3_ODR, odr);
 
 	ret = _interface->set_reg(odr_ctl_reg, BMP3_ODR_ADDR);
 
@@ -388,7 +368,7 @@ BMP388::set_sensor_settings()
 	}
 
 	uint8_t iir_ctl_reg = 0;
-	iir_ctl_reg = BMP3_SET_BITS(iir_ctl_reg, BMP3_IIR_FILTER, _iir_coef);
+	iir_ctl_reg = BMP3_SET_BITS(iir_ctl_reg, BMP3_IIR_FILTER, iir_coef);
 	ret = _interface->set_reg(iir_ctl_reg, BMP3_IIR_ADDR);
 
 	if (ret != OK) {
@@ -589,13 +569,20 @@ BMP388::get_sensor_data(uint8_t sensor_comp, struct bmp3_data *comp_data)
 	bool result = false;
 	int8_t rslt;
 
-	uint8_t reg_data[BMP3_P_T_DATA_LEN] = { 0 };
+	uint8_t reg_data[BMP3_P_T_DATA_LEN];
-	struct bmp3_uncomp_data uncomp_data = { 0 };
+	struct bmp3_uncomp_data uncomp_data;
 
-	rslt = _interface->get_reg_buf(BMP3_DATA_ADDR, reg_data, BMP3_P_T_DATA_LEN);
+	rslt = _interface->get_reg_buf(BMP3_SENS_STATUS_REG_ADDR, reg_data, BMP3_P_T_DATA_LEN);
 
 	if (rslt == OK) {
-		parse_sensor_data(reg_data, &uncomp_data);
+		uint8_t status = reg_data[0];
+
+		// check if data ready (both temp and pressure)
+		if ((status & (3 << 5)) != (3 << 5)) {
+			return false;
+		}
+
+		parse_sensor_data(reg_data + 1, &uncomp_data);
 		result = compensate_data(sensor_comp, &uncomp_data, comp_data);
 	}
 

src/drivers/barometer/bmp388/bmp388.h

@@ -114,7 +114,7 @@
 
 /* Macros related to size */
 #define BMP3_CALIB_DATA_LEN               (21)
-#define BMP3_P_T_DATA_LEN                 (6)
+#define BMP3_P_T_DATA_LEN                 (7)
 
 /* Macros to select the which sensor settings are to be set by the user.
  * These values are internal for API implementation. Don't relate this to
@@ -322,14 +322,15 @@ public:
 
 	void 			RunImpl();
 private:
+	static constexpr uint8_t			osr_t{BMP3_OVERSAMPLING_2X};		// oversampling rate, temperature
+	static constexpr uint8_t			osr_p{BMP3_OVERSAMPLING_16X};		// oversampling rate, pressure
+	static constexpr uint8_t			odr{BMP3_ODR_50_HZ};			// output data rate (not used)
+	static constexpr uint8_t			iir_coef{BMP3_IIR_FILTER_DISABLE};	// IIR coefficient
+
 	PX4Barometer		_px4_baro;
 	IBMP388			*_interface{nullptr};
 
 	unsigned		_measure_interval{0};			// interval in microseconds needed to measure
-	uint8_t			_osr_t{BMP3_OVERSAMPLING_2X};		// oversampling rate, temperature
-	uint8_t			_osr_p{BMP3_OVERSAMPLING_16X};		// oversampling rate, pressure
-	uint8_t			_odr{BMP3_ODR_50_HZ};			// output data rate
-	uint8_t			_iir_coef{BMP3_IIR_FILTER_DISABLE};	// IIR coefficient
 
 	perf_counter_t		_sample_perf;
 	perf_counter_t		_measure_perf;